Bump cffi from 1.12.3 to 1.14.0

Bumps [cffi](https://bitbucket.org/cffi/release-doc) from 1.12.3 to 1.14.0.
- [Commits](https://bitbucket.org/cffi/release-doc/commits)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

requirements.txt

@@ -1,5 +1,5 @@
 atomiclong==0.1.1
-cffi==1.12.3
+cffi==1.14.0
 fusepy==3.0.1
 pycparser==2.20
 pygit2==0.28.2